The Japanese Patent Publication No. 3067656 discloses the temporary storage of articles achieved by suspending a rack from a running rail for an overhead travelling carriage. However, it is difficult for the rack suspended from the running rail to store a large number of articles. In some cases, after an overhead travelling carriage system has been installed, productivity is increased by improving production facilities or increasing the availability factor of the facilities. In these case, it is necessary to enhance the ability to store articles, but available spaces are used for the improvement of the production facilities and the like. Consequently, there remain no spaces to install a stocker. Then, it is contemplated that a rack suspended from the running rail may be introduced. However, such a rack disadvantageously has a small holding capacity.
It is a basic object of the present invention to improve the ability of an overhead travelling carriage system to store articles using a stocker which can deliver and receive articles to and from an overhead travelling carriage and which can store a larger number of articles in a narrow space.